Method of and apparatus for excavating



Oct. 20, 1936. RANNEY METHOD OF AND APPARATUS FOR EXCAVATING Filed Dec. 20, 1935 5 Sheets-Sheet 2 INVENTOR [e0 Pan jay ATTORNEYS m mi hwl ll lH Oct. 20, 1936. L. RANNEY METHOD AND APPARATUS FOR EXCAVATING Filed Dec. 20, 1953 5 Sheets-Sheet s INVENTOR [6'0 Fan/76y m a a 4 w m 1 x \H Oct. 20, 1936. RANNEY METHOD OF AND APPARATUS FOR EXGAVATING File i Dec. 20, 1955 5 Sheets-Sheet 4 m M [m Oct. 20, 1936. L. RA NNEY 2,057,691

METHOD .OF' AND APPARATUS FOR EXCAVATING Filed Dec. 20, 1953 5 Sheets-Sheet 5 [60 Pqnvvey ATTORNEY Patented Oct. 20, 1936 are STATES PATENT, OFFICE Leo Ranney, Morro Bay, Calif. Application December 20, 1933, Serial No. 703,193

24 Claims.

My invention relates to means for excavatingearth material, and particularly to means for excavating appropriate material which usually is unconsolidated, although somewhat consolidated material can likewise be handled.

Some excavating work requiresthe use of casings, and in sinking casings to a considerable depth, say, to eighty or one hundred feet or more, the emcacy of .thewustomary orange-peel orclam-shell bucket rapidly decreases. The time involved fora given job-increases considerably; the hazard to workmen, especially if compressed air is utilized in the casing, is more serious; and the expense per foot of depth increases very rapidly. These difiiculties are due to various causes. I Among others, especially in subaqueous work, is the deleterious factor that much of the earth material is washed out of the bucket as the bucket is passing through the water in the casing, while the mere presence of water in the casing reduces considerably the possible speed of operation of the bucket. The bucket lines are prone to twist, and it is impossible to dig close against the sides of the casing. This latter factor is especially disadvantageous in the event the casing is non-circular. To overcome someof these difiiculties, special excavating machines for the sinking of casings have been developed, but in every instance these machines not only are bulky and initially expensive but are very expensive to operate. They are therefore not practical unless there is a large number of casings to sink at one location, and, even so, they can be used only when conditions are favorable, for instance, in tough, heavy clay. They are not of value ior use in running ground or uicksand and are of no use in instances where the material is likely to cave or heave up in the bottorn'of the hole. There is another alternative for the sinkingof casings of not much more than three feet in diameter. This scheme utilizes a bailing bucket which is of substantially the same diameter as the inside of the casing in order to maintain the bailer or bucket upright while digging. Here, too, the presence of water in the casing considerably restricts the speed of operation, and the necessity for having a relatively large bailer limits the size of casing and, consequently, of the hole which can be dug. Again, anything but circular casings are out of the question for this method of operation.

It is therefore an object of my invention to provide an improved apparatus and method for excavating.

A further object of my invention is to provide a method and apparatus which overcome substantially all of the difilculties herelnabove enumerated.

An additional object of my invention is to provide a method and apparatus for sinking 9. casing of virtually any sizethrough unconsolidated or somewhat consolidated material, without limitat-ion with respect .to depth and with considerably greater economy than with any method or apparatus heretofore known.

A further object of my invention is to provide an apparatus for excavating which is useful in connection with my method and which is initial- 1y inexpensive to construct.

The foregoing and other objects will appear from the embodiment of the invention as set forth in the drawings, in which-- Figure 1 is a schematic view, portions being in cross-section and portions being in elevation, showing the apparatus of my invention as it apgo pears in an excavating job in sinking a casing.

Figure 2 is a schematic view, portions being in cross-section and portions being in elevation, showing a modified form of my apparatus as it appears in an excavating job of a different character.

Figure 3 is, on the left half, a side elevation, and on the right half, a cross-section on a diametral plane, of a drill bit and associated mechanism constructed in accordance with my in- 80 vention.

Figure 4 is a cross-section the plane of which is indicated by the line i4l of Figure 3.

Figure 5 is a cross-section the plane of which is indicated by the line 5-5 of Figure 3.

Figure 6 is a bottom plan of thedrill bit shown in Figure 3.

Figure '7 is a cross-section on a diametral plane of a modified form of drill bit in accordance with my invention. 4

Figure 8 is a cross-section the plane of which is indicated by the line 8-8 of Figure '7.

Figure 9 is a cross-section on a diametral planeof a further modified form of drill bit in accord- 'ance with my invention.

Figure 10 is a cross-section the plane of which is indicated by the line Ifl-lll of Figure 9.

Figure 11 is, in general, a cross-section on a diametral plane of an additionally modified form of drill bit in accordance with my invention.

Figure 12 is a cross-section the plane of which is indicated by the line l2-I2 of Figure 11.

Figure 13 is a cross-section on a diametral plane at right angles to the plane of section of Figure 11, showing the modification of Figure 11 in accordance with my invention.

Figure 14 is a transverse cross-section the plane sired cross-sectional shape, whether round or ure 13. g I

In its preferred form, the apparatus of my invention includesa drill adapted to reciprocate and to be supplied with fluidunder pressure, to remove, through a suitable channel, the excavated material by means of the fluid lift principle, either alone or in conjunction with liquid jets for assisting in dislodging the material to be ex-" cavated and in discharging such material.

The preferred form of the apparatus of my invention and the method of practising the same are utilized in conjunction with material 6 to be excavated, which is of an unconsolidated or somewhat consolidated character and is located at a considerable depth below the surface! of a body of water 8. If the waterl is subterranean, the surface I is the ordinary water table. Adjacentthe water 8 there is an elevation 8, either natural, such as the ground or a bank, or artificial such as a wharf or pier.

In following my invention, according to one modification I preferably sink a casing If of any suitable type and construction and of any-de non-circular being immaterial. The casing is rested upon the surfaceof the material 8 and extends upwardly above the level of the water table I. 1- preferably flll the interior of the casing to an appropriate height with liquid such as water or muddy water, by any convenient means. In

Figure 1 there is diagrammatically represented a pump l2 drawing from a pond |8 and driven g ly thereof,-and of sufllcient pressure to assist in maintaining in position the material 8 surrounding the excavation.

The flow of fluid from the interior of the cas= ing generally outward and upward exteriorly of the bottom thereof is sumcient to lubricate the entering portion of the casing where ordinarily the casing would contact the surrounding material. Lubrication by such liquid is especially effective where the casing is forced through materialhaving a tendency to cave, since usually under such circumstances the skin friction is excessive; but by maintaining a flow of water generally upward over the lower portion of the exterior of the casingr uch material is maintained away fromthe surface of the casing and the skin friction is radically reduced. Furthermore, in the event the casing is in cavey or sandy material and it is desired to maintain such material virtually in place and out of the excavation, relalowered-into the formation 8,-and in order that a suitable excavation can be made, I preferably locate, in a suitable place 'a drill rig, generallydesignated |'|,'wh'ich in the present instance ins cludes a transporting truck l8 on, which a boom is is mounted for universal orientation. The boom is provided-with the customary controls and is likewise provided with a drill line 2| which is suitably reciprocated by rotating idler 22 and. passes over a pulley 28 at the outer end of a drfll structure generally designated 21. stem 26 is provided with an attachment 28 to which is secured the operating line 2|, so thatupon rotation of the idler 22 the drill structurewith and'cut and excavate the material in the bottom of the casing I That is, the up-anddown churning and cutting movement of the bit is effective to dislodge, chop up or cut and break up the material from the surrounding formation.

7 The vertical reciprocation of the bit also produces a lateral surging and turbulence of the 'water' under the bit. which helps to erode and dislodge the material to be excavated. Because of the universal orientation of the boom I8, the drill structure 21 can be moved to any desired location within the casing vI I, so that excavation can be carried out at any desired point, close to the casing walllor otherwise, in order to provide a proper hole. The cutting function of the drill bit is especially valuable in piercing a -stratum of clay to a sand stratum beneath. Excavation of the underlying sand facilitates thecaving and collapse of the clay layer and thus expedites its removal. It isythus feasible to operate with casings which are not circular in cross-section, and particularly is the maneuverability of the drill valuable in the event the cutting edge of the casing should-strike a boulder or other impediment,

in which instance the drill can excavate the material from beneath the boulder, permitting it to fall inwardlyout'of the way of the cutting edge. In order to remove from the excavation the material which is excavated by the drill bit 29,

and in order to maintain such removal inexpensively and ata rapid rate, I preferably provide a duct 82 leadingfrom a suitable source of fluid under pressure, such as air or steam, and connecting through a suitable flexible connection 33 with a conduit 84 running parallel with the drill structure 21, and, particularly as shown in Figure 3, at a convenient point above the drill bit 29 connecting by means of a fitting 36 with an annular chamber 3 within the drill body 38 and in part defined by a discharge conduit 4|. Fluid such as air under pressure which is conducted through the connected conduits is discharged into the annular space 31, from whence discharge takes place through a plurality of apertures 42 which preferably pierce the wall of the discharge pipe 4| at an inclination not only to the horizontal but likewise to the axis of the discharge pipe, so that the air jets thereby formed produce a swirling motion within the discharge pipe 4|. The churning movement of the drill structure maintains the discharging material in an agitated and fluid condition.

The pipe 4| communicates with a plurality of slots 43 in'the drill bit, the slots being disposed preferably between radial flns 44 projecting from the main body of the drill bit. Thus, as the drill 1|) the boom. Associated with the pulley structure i is a guide 24 for a drill stem 28 forming part of The I churns into the formation, portions thereof pass upwardly through the slots 43, particularly as the drill descends, and are caught up in an upwardly moving current of liquid and air mixed and thus, by means of the air lift, are carried upwardly through the discharge pipe 41, not only by virtue of the air present therein but likewise due to the hydrostatic pressure thereon, and are discharged from the structure through an elbow lit terminating in a length of flexible hose 61 which discharges in a dump $8. The mixture of liquid and excavated material discharged at the dump separates into a pile of excavated material and water, which latter returns to the pond I3 for re-use if desired. Addition of suitable material either from the dump 38 or otherwise, to the water in the pond 53, can be resorted to, if necessary, for mudding off. There is therefore provided, in accordance with my invention, an apparatus for excavating the material at the bottom'oi a casing, the extraneous, non-excavated material being maintained in place by high aqueous pressure and/or mudding d, and means for removing the excavated material by means of the fluid lift mechanism to a suitable point of discharge.

In the operation of this structure, the excavating action is carried on until it is necessary to add additional length of drill structure and additional length of casing, both of which are done in the customary fashion for these jointed structures. In the event the formation is sand or sandy material, there is little difflculty in continuing indefinitely with the excavation, but in the event boulders or large rocks are encountered which cannot be broken by the churning of the drill bit, I preferably let such boulders and rocks accumulate at the bottom of the excavation; then, when there are suficient to justify the action, the drill structure is withdrawn or moved aside and an orange-peel or clam-shell bucket is lowered into the casing to remove the accumulated rocks and boulders, after which the drill resumes its excavating action as heretofore described.

In many cases excavation is carried on without the use of casings. As one of the many examples of such work, there is illustrated in Figure 2 a scheme especially useful in recovering valuable material such as gold-bearing gravel. In this environment the ground level is generally designated 6 and overlies bed rock i above which is situated the material 8' to be excavated. The normal water table Q is considerably below the ground level 6'. In carrying out my invention I utilize a barge ii heating on a natural or artificial body it of water, which, in the latter case, can be supplied from a well pump it extending to the water table a. Since the apparatus of my invention is capable of excavating to a considerable depth, and since the ordinary dredge is limited in working depth, it is often expedient to mount my apparatus on the rear of a dredge which is represented by the barge ii.

The apparatus includes a drill boom i8 carrying a drill structure it which is suitably reciprocated. The drill structure includes a drill bit it, of a type similar to that illustrated in Figure 1, which is supplied with air or other fluid under pressure through a line ii extending-from a suitable source. The churning and cutting action of the drill bit dislodgesthe material to be excavated, in this case the material 8', which is conducted through the drill structure id to a suitable point of discharge by the fluid or air lift described in detail in connection with Figure 1. If required, some of the excavated material, or

even suitable material from anothr source, can be used to mud off the walls of the pond I? in order to maintain therein a water level higher than the water table 9'.

In certain types of formation, particularly in clay material, I have found that the progress of excavation can be accelerated by the use of a jet of fluid such as steam, water or muddy water in addition to the fluid or air lift. Under such circumstances, I preferably provide the drill structure with a conduit 5! for conducting such liquid, which conduit connects by a fitting 52 with a pipe 53 passing through the annular space 31 and discharging into an annular space 56 which is isolated from the remainder of the drill body by annular barriers 56 and 51. The barrier 87 is preferably formed integrally with the drill bit and is pierced by a plurality of ducts 58 each of which terminates in a discharge orifice 59 adjacent one of the drilling fins or webs it and is inclined in a suitable direction to assist in washing loose the material to be excavated. The orifices 59 can be supplied with fluid intermittently or continuously, depending upon the operating conditions.

Under certain conditions oi operation, and particularly with certain formations, I have found it feasible to dispense with the use of compressed air as a lifting medium. Under such circumstances, I preferably use a drill bit substantially as shown in Figures '7 and 8. In this instance, the outer casing ll surrounds a discharge pipe 12. Fastened to both of these pipes is a drill head I3 incorporating a plurality of cutting fins it. Communication from the exterior to the discharge pipe 12 is established by means of a plurality of apertures 16 preferably located intermediate the fins Id. In order to facilitate the discharge of material which is removed by the drill, I provide a jet of liquid such as water, or water and mud. To this end a conduit ll, leading from any suitable source, extends between the outer jacket ii and the inner pipe I? and terminates in an annular barrier or ring 18. Communicating with the conduit TI is an annular chamber 79 which in turn leads into a plurality of es 8i piercing the material of the drill head. These passages preferably unite in a horizontal duct 52 in the lower portion of the drill head and in turn communicate with a suitable nozzle 83 which is disposed axially oi the drill bit and is adapted to discharge upwardly into a diverging difiusing chamber 85. The velocity of efliux of the material from the nozzle 83 is effective to establish a vacuum to induce flow of excavated material and liquid through the aperture is and to impel such material upwardly in the discharge pipe V2 to be relieased from the mechanism at any appropriate po nt.

Under certain other conditions of operation, particularly in rather heavy clay, I have found it advisable to provide a drill bit substantially asshown in Figures 9 and 10. In this instance, the drill head bi is connected to an outer shell 82 and to an inner shell $33, as before. Between the shells is disposed a liquid conduit M which leads into an annular chamber 86 defined by a barrier ti and by the upper terminus of the drill body 8!. Communicating with this annular chamber is a plurality of passages 88 which pms through the drill body and merge into a common chamber 39. Situated on a nipple dd communicating with the chamber 88 is a nozzle ti pierced by a plurality of Jet orifices $2 each of which is diand can be directed to jet under the cutting shoe I of a casing to reduce skin friction. Since the direction of the jets is upward, material such as clay is broken on upwardly. This action is very effective, due to the absence of backing or support above the clay, in distinction to jetting downwardly into a solid, well supported clay mass.

For certain other uses, particularly 'where it is desired to excavate along a generally horizontal plane, especially in excavating value-bearing gravel adjacent the bottomaoi a dredge operation, such, for instance, as shown in Figure 2, I preferably provide my apparatus with a drill bit substantially as shown in Figures 11 to 14 inclusive. In this instance, the drill head I0! I is'oi' generally cylindrical shape with a relatively'flat bottom. It likewise is provided with a plurality of axially disposed, radially-extending flns I02. The interior of the body is contoured to provide a passage Iil communicating with a suitable discharge pipe and is preferably upwardly flared to provide a conical diflusing chamber I06. Discharging into the chamber I05 is a liquid nozzle I01 which communicates by means of a transverse passage IIlB with a plurality of supply passages I09 connected to a source of liquid under pressure, as hereinabove indicated. Intersecting the conical difi'using chamber I08 is a plurality of ducts III which, instead of emerging from the sides of the drill body, emerge therefrom in the bottom portion, so that in use the entrance to the passages or ducts III is as close as possible to a horizontal layer 0! material to be excavated. In the operation of this form of the structure, liquid discharging from the nozzle induces flow inwardly through the ducts I II and is eflectlve to excavate material, during the operation of the drill bit, from substantially a. horizontal plane.

I claim:

1. A method of excavating comprising establishing a desired liquid level above the material to be excavated, dislodging andpreparing said material at least partially by upwardly directed liquid jets, mixing the prepared material with a uid level above said material, dislodgiug and penetrating said clay stratum by successive impacts thereon, mixing said dislodged clay material with a carrier fluid, driving said clay mixture by fluid pressure upward through but isolated from said liquid to a point of discharge,

sembly above the same, causing the assembly to fall successively upon and into the dislodged material, thereby breaking-up and churning the same, mixing the churned material with a'carrier fluid outside the assembly, moving the mixture by suction into the assembly, further mixing and agitating material and carrier fluid within the assembly, moving the mixture into a discharge conduit surrounded by liquid to a desired level, driving the mixture by fluid pressure upward and out of the discharge conduit. moving the assembly from one desired location to another in any direction within the excavation, holding the same in any location for a controlled period of time, and .forcing the assembly into co-operative relationship with undisturbed material to be excavated, to dislodge the same.

4. Claim 3, and replacing with-added liquid the liquid removed from the space Just outside the assembly.

5. Claim 3, in which additional fluid is added to the mixture within the assembly.

6. Claim 3, in which a'whirling motion in the discharge conduit is caused by the introduction of the added fluid.

7. Claim 3, and driving'into the assembly, by the force of the impacts. a part of the material to be excavated.

8. Claim 3, in which a turbulence is created, due to the form of the assembly, between the assembly and the undisturbed material.

9. Claim 3. in which operations on the materialare facilitated by the use of Jets.

10. Claim 3, in which a portion of the discharge is returned to the excavation.

11. Claim 3, in which said suction is induced by lightening the column in'the discharge conduit.

12. Claim 3, in which the flnal upward movement of the mixture is induced by lightening the column within the discharge conduit.

13. A method of excavating comprising, directing a jet of liquid against the material to be excavated, to dislodge the same. the direction of said jet being flxed above the horizontal so as to attack the material from below, giving it a cavity to break to on two sides, moving the jet about on the face oi the undisturbed material, flxing the position 01' the jet with respect to the face at any point for a controlled period of time, dislodging the attacked material and removing the same. 14. Claim 13, and removing said material by suction.

15. Claim 13, in which the dislodged material is further disintegrated and mixed with a carrier fluid before-being removed from the excavation. 16. Claim 13, in which the removal means is kept from clogging by Jet action.

17. Claim 13 in which the dislodged material is removed through a removal assembly with an intake, and in which the jets perform the double function of keeping the removal assembly free from clogging at the intake, and at the same time attacking the material to be excavated.

18. An excavating apparatus comprising, in assembly, a reciprocating hollow bit and drill stem combination, means for reciprocating the same, means to reduce .fluid pressure within the assembly, a conduit to conduct fluid downward to the lower part of the assembly, means to dislodge and agitate thematerial to be excavated,

means to mix the same with a carrier fluid outside the assembly, meaim to bring said mixture within control of the assembly, means to further mix material and carrier fluid within the assembly, another upwardly extending discharge conture upward and from said conduit, means to hold the assembly in a positively controlled desired operating position, means to move the assembly from place to place within the excavation, in any direction, all in co-operative relationship, and means to operate the entire apparatus.

19. Claim 18, in which the drill stem is hollow and is designed as the upward or discharge conduit.

20. Claim 18, and means to direct the descending fluid into the discharge conduit at an angle upward to the axis thereof.

21. Claim 18, in which apertures are provided in the wall of the bit for the entrance oi material thereinto.

22. Claim 18, in which cutting fins are attached to the bit.

23. Claim 18, in which the body of the bit is conical or wedge shaped at its impacting end.

24. Claim 18, and means to introduce a liquid and means to introduce a gas into the carrier fluid within the assembly.

LEO RANNEY. 

